Development of volcanic pumice based cement and lightweight concrete

摘要

The results of investigations on the suitability of using volcanic pumice (VP) as cement replacement material and as coarse aggregate in lightweight concrete production are reported. Tests were conducted on cement by replacing 0-50% of cement by mass and on concrete by replacing 0-100% of coarse aggregate by volume. The physical and chemical properties of VP were critically reviewed to evaluate the possible influence on both fresh and hardened properties of cement and concrete. The standard tests on different mixtures of Portland cement and volcanic pumice powder (VPP) mixtures provided encouraging results, comparable to those for blended Portland fly ash cement, and showed good potential for manufacturing Portland volcanic pumice cement with higher setting time and low heat of hydration using up to 15% of VPP. The properties of volcanic pumice concrete (VPC) using different percentages of volcanic pumice aggregate were evaluated by conducting a comprehensive series of tests on workability, strength, shrinkage and permeability. It is concluded that VPC has sufficient strength and adequate density to be accepted as structural lightweight concrete. Design charts are presented to evaluate mix design parameters of VPC.